CHM ENG 142 Study Guide - Midterm Guide: Reaction Rate Constant, Reversible Reaction, Rate Equation

10. Consider the following mechanism. Step 1: 2NO(g) → NO2(g) Step 2: N202(g) + H,(g)-→ N20(g) + H2O(g) a. Write the equation of the overall reaction for which this reaction is valid. b. Identify all intermediates in the mechanism. Determine the molecularity of each elementary step in the mechanism. c. The observed rate law for the overall reaction is Rate k[NO12. Which of the elementary steps is the rate-determining step? Explain. d. Draw a reaction diagram consistent with this mechanism, given that the reaction is endothermic. e.

One overall reaction through which O, is depleted in the stratosphere is: 0,0 +0 – 2020 We will consider this reaction in that absence (uncatalyzed) and presence (catalyzed) of Cl atom. (1) Mechanism of the uncatalyzed reaction The experimentally observed rate law is: rate = k [0][0]. 1. For each of the following mechanisms, derive the rate law, and state where it agrees with the experimentally observed, phenomenological, rate law given above. (a) (2 pt) 0,0 +0. – 2020 (single step mechanism) B 2018 Rate law: _KT03]ī6) Rate law: Agrees with experimentally observed rate: yes) no (circle one) (b) (2 pt) 0,0 +0000 (slow) (fast) ki04)= = AIU23, di04) KIZU3I7o]-K TO+]-o KIT03770 K2 Rate law: K, LO3) IO) Agrees with experimentally observed rate: (yes) no (circle one) (C) (2 pt) (fast, reversible) (slow) 0, 0+0 40 sie Omg * O, KI2010 Kil03) T0] = K, L04] 104]: Κ. 20 ]το) K-2 rate - Ki K2 LO, ITO) KH. Rate law: = KI 0:770) Agrees with experimentally observed rate: yes) no (circle one) Homework 5 Page 1 of 3

13. The rate of the reaction A + 2B → C, was studied by the initial rate method and the following data were A] (M) 0.10 0.30 0.10 BI (M) 0.40 0.40 0.10 Rate (M/s 64 64. 2 4.0 What is the rate law for the reaction? A. rate k[A[B] B. rate k[Aj2 C. rate = k[A][B] D. rate-k[B]2 E. rate k[AB 14. A reaction with the stoichiometry A + B → C is studied by measuring [A] as a function of time. A plot of [A]vs. time is nonlinear A plot of In(IA] s. time is linear with a slope of -3.0 /s A plot of 1/A] vs. time is nonlinear What is the order of the reaction with respect to [A] and what is the rate constant? Order with respect to [A] A. B. C. D. E: Rate constant -3.0 s-1 3.0 M-1 s-1 3.0 s-I 0.33 M s 3.0 M-1 s- 15. A reaction proceeds by the single step mechanism (elementary step) A + B → C a. What is the molecularity of the reaction? b. What is the rate law of the reaction? Molecularity Rate Law A. Bimolecular B. Unimolecular C. Bimolecular D. Bimolecular E. Unimolecular Rate k(B2 Rate-k[AJB] Rate k[A][B) Rate-k[A Rate k[A